Effect of copper on the photosynthesis and growth of Eichhornia crassipes.

Although copper is essential for plant growth and development and plays an important role in many physiological processes, excess copper, resulting from industrial development and population expansion in the recent decades, leads to environmental pollution and has been a cause of wide concern for the adverse effects on photosynthesis, metabolism and growth of plants. The growth properties (e.g. fresh weight, root length, height), photosynthetic properties (e.g. gas exchange, chlorophyll a fluorescence, chlorophyll content) and the physiological index (e.g. activity of antioxidant enzymes and osmotic regulators) of Eichhornia crassipes were assessed under various Cu2+ concentrations in hydroponic experiments. The growth of E. crassipes was negatively affected by Cu2+ treatments, especially at higher Cu2+ concentrations; the Cu2+ treatments resulted in decreased photosynthesis because of a decrease in leaf chlorophyll content and damage to PSII functions, except the oxygen-evolving complex. The physiological tolerance of E. crassipes to Cu2+ relies on osmotic regulation, anti-lipid peroxidation and improved antioxidant properties. The results indicate that E. crassipes could be considered as a phytoremediation agent for Cu2+ pollution in aquatic environments. However, the benefit of E. crassipes for Cu2+ removal in a highly polluted aquatic environment will be limited, but it will be effective in remediating sites with low pollution (≤5 mg·l-1 ). The present results could provide not only a basis for understanding the effects of pollutants on photosynthesis in plants under heavy metal stress but also provide a basis for choosing plants for phytoremediation.

c-Fos-Regulated Matrix Metalloproteinase-9 Expression is Involved in 17ß-Estradiol-Promoted Invasion of Human Endometrial Stromal Cell.

Endometriosis is a frequent gynecological disease associated with severe pain and infertility. Although its dependency on estrogen is well recognized, the molecular mechanism along the estrogenic pathway has not been fully understood. This study investigates the effect of 17ß-estradiol (E2) on human endometrial stromal cell (HESC) invasion and the role of c-fos and matrix metalloproteinase-9 (MMP-9) in mediating the biological function of 17ß-E2. It is found that 17ß-E2 promotes not only HESC invasion, but also c-fos and MMP-9 expression in HESC. Further experiments demonstrate that the estrogen receptor inhibitor ICI 182780 and siRNA-mediated c-fos or MMP-9 knockdown are able to block the effect of 17ß-E2 on HESC invasion. Moreover, siRNA-mediated c-fos knockdown suppresses the effect of 17ß-E2 on MMP-9 expression. Our results indicate that 17ß-E2-induced HESC invasion is dependent on c-fos-mediated MMP-9 expression. These findings facilitate our understanding on the pathogenesis of endometriosis and may provide data potentially useful for the development of new treatment modalities for better management of endometriosis.

The diagnostic accuracy of high-mobility group box 1 protein and twelve other markers in discriminating bacterial, viral and co-infected bronchial pneumonia in Han children.

Pneumonia in children is common and can lead to grave consequences if not addressed in a proper and timely manner. In the management of pneumonia, early identification of the causative infective agent is of obvious importance for treatment, as it allows selection of the appropriate antibiotics. However, such identification requires laboratory test results, which may not be immediately available. The aim of this study was to evaluate the accuracy and usefulness of 13 markers in differentiating between viral and bacterial pneumonia in Han children (34 healthy controls and 78 patients). It was found that WBC counts were more accurate in diagnosis of the type of agent responsible for infection than was the degree of expression of HMGB1. Among the 13 markers investigated, HMGB1 was the best at discriminating between co-infected (bacterium and virus) and single-infected (bacterium or virus) children with bronchial pneumonia. HMGB1 expression of less than 1.0256, excluded most co-infections (the negative predictive value was greater than 89.7%). Diagnosed sole viral pneumonia clinically overlapped with bacterial pneumonia, but bacterial pneumonia was more often associated with higher white blood cell (WBC) counts (WBC ≥ 13,000 cells/mm(3)). When the two marker readouts--HMGB1 < 1.0256 and WBC ≥ 13,000 cells/mm(3)--were combined, the positive predictive value for bacterial pneumonia alone was 92.3%. These findings can help clinicians discriminate between bronchial pneumonia caused by virus, bacterium or both with a high specificity.

Enhanced anthocyanin production by repeated-batch culture of strawberry cells with medium shift.

Repeated-batch cultures of strawberry cells (Fragaria ananassa cv. Shikinari) subjected to four medium-shift procedures (constant LS medium, constant B5 medium, alternation between LS and B5 starting from LS and alternation between LS and B5 starting from B5) were investigated for the enhanced anthocyanin productivity. To determine the optimum period for repeated batch cultures, two medium-shift periods of 9 and 14 days were studied, which represent the end of the exponential growth phase and the stationary phase. By comparison with the corresponding batch cultures, higher anthocyanin productivity was achieved for all the repeated-batch cultures at a 9-day medium-shift period. The average anthocyanin productivity was enhanced 1.7- and 1.76-fold by repeated-batch cultures in constant LS and constant B5 medium at a 9-day shift period for 45 days, respectively. No further improvement was observed when the medium was alternated between LS (the growth medium) and B5 (the production medium). Anthocyanin production was unstable at a 14-day shift period regardless of the medium-shift procedures. The results show that it is feasible to improve anthocyanin production by a repeated-batch culture of strawberry cells.